> Source: [sk168797](https://support.checkpoint.com/results/sk/sk168797)

# sk168797 - Traffic routes out of the wrong interface after updating an SMB image with ISP redundancy configured

| Property | Value |
|----------|-------|
| Solution ID | sk168797 |
| Date Created | 2020-08-20 |
| Last Modified | 2020-09-29 |
| Technical Level | Advanced |
| Products | Spark Firewall (Locally Managed) |
| Versions | R82.00.X, R81.10.X |
| Platform | 910 |

## Symptoms

- Traffic does not route out of the correct interface as per ISP advanced configuration `use as default route`. The issue does not occur if the user disables this on one of the ISP redundancy configured links.

<br />

## Cause

A routing priority change occurred between versions:  

* Non-Working Build: R77.20.87 Build 990173004
* Working Build: R77.20.87 Build 990172960

The following is an **example** of test output when the WAN and the DMZ interface both participate in ISP redundancy:  

`[vs_0][fw_0] DMZ:o[84]: 2.2.2.2 -> 1.1.1.1 (ICMP) len=84 id=8119`  
`ICMP: type=8 code=0 echo request id=23908 seq=1276`  
`[vs_0][fw_0] WAN:O[84]: 2.2.2.2 -> 1.1.1.1 (ICMP) len=84 id=8119`  
`ICMP: type=8 code=0 echo request id=23908 seq=1276`

If you disable ISP redundancy on the DMZ interface and on the FW Monitor, the traffic starts to correctly go out though the DMZ interface:  

`[vs_0][fw_0] DMZ:o[84]: 2.2.2.2 -> 1.1.1.1 (ICMP) len=84 id=8235`  
`ICMP: type=8 code=0 echo request id=23908 seq=1392`  
`[vs_0][fw_0] DMZ:O[84]: 2.2.2.2 -> 1.1.1.1 (ICMP) len=84 id=8235`  
`ICMP: type=8 code=0 echo request id=23908 seq=1392`

<br />

## Solution

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